Composition and method for preparing novel cationic thickeners

ABSTRACT

A composition and method for a linear or crosslinked cationic polyelectrolyte, involving copolymerization of at least one cationic monomer with at least one neutral monomer and at least one-nonionic surfactant monomer.

The subject of the invention is novel polymers, their method ofpreparation and their use as thickening and/or emulsifying agent.

The thickening of aqueous phases is generally carried out byincorporating therein hydrophilic polymers of all sorts, whether theyare synthetic or of natural origin.

Among the polymers of natural origin, xanthan or guar gums are fairlywidely used. They however have the conventional disadvantages of naturalproducts, namely a fluctuating quality and price.

Among the hydrophilic synthetic thickeners most widely used are polymersin the form of self-reversible invert latexes or powders. They are usedin a wide pH range and are often well tolerated by humans. Suchcompositions are described for example in French patents and patentapplications published under the numbers 2721511, 2773805, 2774688,2774996, 2782086, 2785801, 2786493, 2787457, 2789395, 2794034, 2794124,2808446, 2808447 and 2810883.

These polymers are anionic and are essentially intended to thickenand/or emulsify cosmetic, dermo-pharmaceutical or pharmaceutical topicalformulations which contain numerous constituents such as oils, nonionicor anionic surfactants, inorganic salts and/or weak acids.

Some formulations, in particular those intended for hair care, alsocontain cationic surfactants and/or cationic conditioning polymers. Inthis particular case, thickeners consisting of anionic polymers are notrecommended because of electrostatic interactions between the positiveand negative charges which cause precipitation of the polymer, andcationic thickening polymers such as those described in American patentspublished under the numbers U.S. Pat. No. 4,806,345 and U.S. Pat. No.5,100,660 are preferably used.

Although the latter behave satisfactorily in an acidic medium and arecompatible with cationic surfactants, they nevertheless lose theirthickening power in formulations high in electrolytes.

Accordingly, the applicant focussed on developing novel thickeners of acationic nature, which are compatible with cationic surfactants whilepreserving their thickening power in media high in electrolytes.

According to a first aspect, the subject of the invention is a linear orcrosslinked cationic polyelectrolyte, characterized in that it isobtained by copolymerization of at least one cationic monomer with atleast one neutral monomer and at least one nonionic surfactant monomer.

The expression crosslinked polyelectrolyte denotes a nonlinearpolyelectrolyte which exists in the form of a three-dimensional networkwhich is insoluble in water, but which is capable of swelling in waterand therefore leading to the production of a chemical gel.

The expression copolymerization means, in the context of the presentinvention, that the polymerization reaction uses at least threedifferent monomers. It can however involve more than three differentmonomers.

The expression neutral monomer denotes monomers not containing anystrong or weak acid functional group or any positively charged group.They are more particularly chosen from acrylamide, methacrylamide,vinylpyrrolidone, diacetoneacrylamide, dimethylacrylamide,(2-hydroxyethyl) acrylate, (2,3-dihydroxypropyl) acrylate,(2-hydroxyethyl) methacrylate, (2,3-dihydroxypropyl) methacrylate or anethoxylated derivative having a molecular weight of between 400 and1000, of each of these esters.

The expression cationic monomers denotes more particularly monomerscontaining a quaternary ammonium functional group. They are moreparticularly chosen from2,N,N,N-tetramethyl-2-[(1-oxo-2-propenyl)amino]propanammonium chloride(AMPTAC), 2,N,N-trimethyl-2-[(1-oxo-2-propenyl)amino]propanammoniumchloride, N,N,N-trimethyl-3-[(1-oxo-2-propenyl)amino]propanammoniumchloride (APTAC), diallyldimethylammonium chloride (DADMAC),N,N,N-trimethyl-2-[(1-oxo-2-propenyl)]ethanammonium chloride,N,N,N-trimethyl-2-[(1-oxo-2-methyl-2-propenyl)]-ethanammonium chloride,N-[2-(dimethylamino)-1,1-dimethyl]acrylamide,N-[2-(methylamino)-1,1-dimethyl]acrylamide, 2-(dimethylamino)ethylacrylate, 2-(dimethylamino)ethyl methacrylate orN-[3-(dimethylamino)propyl]-acrylamide.

The expression nonionic surfactant monomer denotes more particularly thepolyalkoxylated derivatives of esters of monomers containing a weak acidfunctional group with fatty alcohols. Such compounds are representedeither by general formula (I):A-C(═O)—O—[(CH₂—CH(R₁)—O]_(n)—R  (I)or alternatively by general formula (I′):R′—[O—CH(R′₁)—CH₂]_(n)—O—(O═)C-A′-C(═O)—O—[(CH₂—CH(R₁)—O]_(n)—R  (I′)in which formulae (I) and (I′):

n and n′ represent, independently of each other, a number between 1 and50;

A represents an unsaturated aliphatic monovalent radical comprising from2 to 6 carbon atoms,

A′ represents an unsaturated aliphatic divalent radical comprising from2 to 6 carbon atoms,

R₁ and R′₁ represent, independently of each other, a hydrogen atom, amethyl radical or an ethyl radical; and

R and R′ represent, independently of each other, a saturated orunsaturated, linear or branched, aliphatic hydrocarbon radicalcomprising from 8 to 30 carbon atoms.

In formulae (I) and (I′), as defined above, the divalent radicals:—[(CH₂—CH(R₁)—O]_(n)— and —[O—CH(R′₁)—CH₂]_(n)—represent, independently of each other:

either chains composed solely of ethoxyl groups (R₁=H; n>0),

or chains composed solely of propoxyl groups (R₁=CH₃; n>0),

or chains composed solely of butoxyl groups (R₁=C₂H₅; n>0),

or chains composed of at least two different groups chosen from ethoxyl,propoxyl and/or butoxyl groups.

When these chains are composed of different groups, they are distributedright along this chain, in a block or randomly.

The expression unsaturated aliphatic monovalent radical comprising from2 to 6 carbon atoms denotes more particularly for A, the vinyl radical(CH₂═CH—) or the 2-propenyl radical [CH₂═C(CH₃)—].

The expression unsaturated aliphatic divalent radical comprising from 2to 6 carbon atoms denotes more particularly for A′, the 1,2-ethenediylradical (—CH═CH—) or the 2-propene-1,2-diyl radical [—CH₂—C(═CH₂)—].

The expression saturated or unsaturated, linear aliphatic hydrocarbonradical comprising from 8 to 30 carbon atoms denotes more particularlyfor R and R′, the radicals derived from linear primary alcohols such asfor example those derived from octyl, pelargonic, decyl, undecyl,undecenyl, lauryl, tridecyl, myristyl, pentadecyl, cetyl, heptadecyl,stearyl, oleyl, linoleyl, nonadecyl, arachidyl, behenyl, erucyl or1-triacontanoic alcohols. They are in this case octyl, nonyl, decyl,undecyl, 10-undecenyl, dodecyl, tridecyl, tetradecyl, pentadecyl,hexadecyl, heptadecyl, octadecyl, 9-octadecenyl, 10,12-octadecadienyl,13-docosenyl or triacontanyl radicals.

The expression saturated or unsaturated, branched aliphatic hydrocarbonradical comprising from 8 to 30 carbon atoms denotes more particularlyfor R and R′,

either the radicals derived from Guerbet alcohols, which are branched1-alkanols corresponding to general formula:CH₃—(CH₂)_(p)CH[CH₃—(CH₂)_(p-2)]—CH₂OH,in which p represents an integer between 2 and 14, such as for examplethe 2-ethylhexyl, 2-propylheptyl, 2-butyloctyl, 2-pentylnonyl,2-hexyldecyl or 2-octyldodecyl radicals;

or the radicals derived from isoalkanols corresponding to generalformula:CH₃—CH(CH₃)—(CH₂)_(m)—CH₂OH,in which m represents an integer between 2 and 26, such as for examplethe 4-methylpentyl, 5-methylhexyl, 6-methylheptyl, 15-methylpentadecylor 16-methylheptadecyl radicals;

or the 2-hexyloctyl, 2-octyldecyl or 2-hexyldodecyl radicals.

The subject of the invention is more particularly a cationicpolyelectrolyte as defined above, characterized in that the nonionicsurfactant monomer is chosen from the compounds of formula (I) or thecompounds of formula (I′) as defined above, in which:

R and R′ represent, independently of each other, a saturated orunsaturated, linear or branched, aliphatic hydrocarbon radicalcomprising from 8 to 18 carbon atoms,

R₁ and R′₁ each represent a hydrogen atom, and

n and n′ represent, independently of each other, a number between 1 and10.

The subject of the invention is more particularly a cationicpolyelectrolyte as defined above, characterized in that:

from 5% to 35% of the monomeric units which it comprises is a cationicmonomer,

from 55% to 95% of the monomeric units which it comprises is a neutralmonomer, and

from 0.1% to 5% of the monomeric units which it comprises is asurfactant monomer.

According to another particular aspect of the present invention, itssubject is a cationic polyelectrolyte as defined above, characterized inthat it is obtained by copolymerization of at least one cationic monomerwith at least one neutral monomer, at least one nonionic surfactantmonomer and a non-zero proportion ofN-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl)propenamide.

N-[2-Hydroxy-1,1-bis(hydroxymethyl)ethyl]propenamide, also calledtris(hydroxymethyl)acrylamidomethane or THAM:

is described in European patent application published under the numberEP 0 900 786.

When the polyelectrolyte which is the subject of the present inventioncontains a non-zero proportion of THAM monomer,

from 5% to 35% of the monomeric units which it comprises is a cationicmonomer,

from 35% to 91% of the monomeric units which it comprises is a neutralmonomer,

from 0.1% to 5% of the monomeric units which it comprises is a nonionicsurfactant monomer, and

from 3% to 20% of the monomeric units which it comprises is the THAMmonomer.

According to another particular aspect of the present invention, thepolyelectrolyte as defined above is not crosslinked.

According to another particular aspect of the present invention, thepolyelectrolyte as defined above is crosslinked. In the latter case, thecrosslinking agent is chosen in particular from diethylenic orpolyethylenic compounds, and most particularly from diallyloxyaceticacid or one of the salts and in particular its sodium salt,triallylamine, trimethylol propanetriacrylate, ethylene glycoldimethacrylate, diethylene glycol diacrylate, diallylurea or methylenebis(acrylamide).

The crosslinking agent is then generally used in the molar proportion,expressed relative to the monomers used, of 0.005% to 1%, in particular0.01% to 0.2%, and more particularly 0.01% to 0.1%.

According to a second aspect of the present invention, its subject is acomposition comprising an oily phase, an aqueous phase, at least onewater-in-oil (W/O) type emulsifying agent, at least one oil-in-water(O/W) type emulsifying agent, in the form of a self-reversible invertlatex comprising from 20% to 70% by weight, preferably from 25% to 40%by weight, of a cationic polyelectrolyte as defined above.

The self-reversible invert latex according to the invention generallycontains from 2.5% to 15% by weight, and preferably from 4% to 9% byweight, of emulsifying agents, of which from 20% to 50%, in particularfrom 25% to 40% of the total weight of the emulsifying agents presentare of the water-in-oil (W/O) type and in which from 80% to 50%, inparticular from 75% to 60%, of the total weight of the emulsifyingagents are of the oil-in-water (O/W) type.

In the self-reversible invert latex as defined above, the oily phasegenerally represents from 15% to 50%, preferably from 20% to 25%, of itstotal weight.

The self-reversible invert latex also contains between 5% and 60% byweight of water and more particularly between 20% and 50% by weight ofwater.

The self-reversible invert latex according to the invention may alsocontain various additives such as complexing agents or chain-regulatingagents.

The expression “water-in-oil type emulsifying agent” denotes emulsifyingagents possessing a sufficiently low HLB value to form water-in-oilemulsions, such as the surfactant polymers marketed under the nameHYPERMER™ such as HYPERMER™ B246, HYPERMER™ B41 or HYPERMER™ 2296 orsuch as sorbitan esters, such as the sorbitan monooleate marketed by thecompany SEPPIC under the name MONTANE™ 80, the sorbitan isostearatemarketed by SEPPIC under the name MONTANE™ 70 or the sorbitansesquioleate marketed by SEPPIC under the name MONTANE™ 83. In the caseof a mixture of water-in-oil type emulsifying agents, the HLB value tobe taken into consideration is that of the said mixture.

The expression “oil-in-water type emulsifying agent” denotes emulsifyingagents possessing a sufficiently high HLB value to give oil-in-wateremulsions such as for example the ethoxylated sorbitan esters such asthe ethoxylated sorbitan oleate containing 20 moles of ethylene oxide,ethoxylated castor oil containing 40 moles of ethylene oxide,ethoxylated sorbitan laurate containing 20-moles of ethylene oxide whichare marketed by the company SEPPIC under the names MONTANOX™ 80,SIMULSOL™ OL 50 and MONTANOX™ 20, respectively, the ethoxylated laurylalcohol containing 7 moles of ethylene oxide marketed by the companySEPPIC under the name SIMULSOL™ P7, the decaethoxylated oleocetylalcohol of ethylene marketed by the company SEPPIC under the nameSIMULSOL™ OC 710 or the polyethoxylated sorbitan hexaoleates marketed bythe company ATLAS Chemical Industries under the names G-1086 and G-1096,ethoxylated nonylphenols.

The oily phase of the self-reversible invert latex described aboveconsists:

either of a commercially available mineral oil containing saturatedhydrocarbons of the paraffin, isoparaffin and cycloparaffin type, havingat room temperature a density between 0.7 and 0.9 and a boiling pointgreater than 180° C., such as for example ISOPAR™ M or ISOPAR™ L, EXXOL™D 100 S marketed by EXXON or the white mineral oils in conformity withthe FDA regulations 21 CFR 172,878 and FR 178,3620(a), such as MARCOL™52 or MARCOL™ 82, also marketed by EXXON;

or of the hydrogenated polyisobutene marketed in France by the companyEts B. Rossow and Co under the name PARLEAM—POLYSYNLANE™ and cited inMichel and Irene Ash; Thesaurus of Chemical products, Chemise PublicitéCos, Ince. 1986 Volume 1, page 211 (ISBN 0 7131 3603 0);

or of the isohexadecane identified in Chemical Abstracts by the numberRN=93685-80-4 and which is a mixture of C₁₂, C₁₆ and C₂₀ isoparaffinscontaining at least 97% of C₁₆ isoparaffins, of which the principalconstituent is 2,2,4,4,6,8,8-heptamethylnonane (RN=4390-04-9), marketedin France by the company Bayer;

or of the isododecane marketed in France by the company Bayer;

or of the squalane which is identified in Chemical Abstracts by thenumber RN=111-01-3 and which is a mixture of hydrocarbons containingmore than 80% by weight of 2,6,10,15,19,23-hexamethyltetracosane. It ismarketed in France by the company SOPHIM, under the name PHYTOSQUALANE™;

or of the fatty acid esters of formula (II):R₁—(C═O)—O—[[CH₂—CH[O—[C(═O)]_(m)—R₂]—CH₂—O]_(n)—[C(═O)]_(p)]_(q)—R₃  (II)in which R₁ represents a linear or branched, saturated or unsaturatedhydrocarbon chain containing from 7 to 30 carbon atoms, R₂ represents,independently of R₁, a hydrogen atom, a linear or branched, saturated orunsaturated hydrocarbon chain containing from 7 to 30 carbon atoms, R₃represents, independently of R₁ or of R₂, a hydrogen atom or a linear orbranched, saturated or unsaturated hydrocarbon chain containing from 1to 30 carbon atoms, m, n, p and q are, independently of each other,equal to 0 or 1, it being understood that when R₃ represents a hydrogenatom, q is different from 0. As compounds of formula (II), there aremore particularly the compounds of formula (IIa):R₁—(C═O)—O—CH₂—CH[O—[C(═O)]_(m)—R₂]—CH₂—O—[C(═O)]_(p)—R₃  (IIa)corresponding to formula (II) as defined above, in which q and n areequal to 1, or a mixture of compounds of formulae (IIa); in this case,they are, preferably,either a compound of formula (IIa₁):R₁—(C═O)—O—CH₂—CH(OH)—CH₂—OH (IIa₁)corresponding to formula (IIa) as defined above, in which m and p areequal to 0 and R₂ and R₃ represent a hydrogen atom,or a compound of formula (IIa₂):R₁—(C═O)—O—CH₂—CH(OH)—CH₂—O—C(═O)—R₃  (IIa₂)corresponding to formula (IIa) as defined above in which p is equal to1, m is equal to 0 and R₂ represents a hydrogen atom,or a compound of formula (IIa₃)R₁—(C═O)—O—CH₂—CH[O—C(═O)—R₂]—CH₂—O—C(═O)—R₃ (IIa₃)corresponding to formula (IIa) as defined above in which m and p areequal to 1,or a mixture of compounds of formulae (IIa₁), (IIa₂) and/or (IIa₃).

As examples of compounds of formulae (IIa₁), (IIa₂) or (IIa₃), there arefor example triglycerides of fatty acids or of mixtures of fatty acidssuch as the mixture of fatty acid triglycerides containing from 6 to 10carbon atoms, marketed under the name SOFTENOL™ 3819, the mixture offatty acid triglycerides containing from 8 to 10 carbon atoms, marketedunder the name SOFTENOL™ 3108, the mixture of fatty acid triglyceridescontaining from 8 to 18 carbon atoms, marketed under the name SOFTENOL™3178, the mixture of fatty acid triglycerides containing from 12 to 18carbon atoms, marketed under the name SOFTENOL™ 3100, the mixture offatty acid triglycerides containing 7 carbon atoms, marketed under thename SOFTENOL™ 3107, the mixture of fatty acid triglycerides containing14 carbon atoms, marketed under the name SOFTENOL™ 3114 or the mixtureof fatty acid triglycerides containing 18 carbon atoms, marketed underthe name SOFTENOL™ 3118, glyceryl dilaurate, glyceryl dioleate, glycerylisostearate, glyceryl distearate, glyceryl monolaurate, glycerylmonooleate, glyceryl monoisostearate, glyceryl monostearate or a mixtureof these compounds.

According to a third aspect of the present invention, its subject isalso a method for preparing a self-reversible invert latex as definedabove, characterized in that:

a) an aqueous solution containing the monomers and the optionaladditives is emulsified in an oily phase in the presence of one or morewater-in-oil type emulsifying agents and nonionic surfactant monomer,

b) the polymerization reaction is initiated by introducing into theemulsion formed in a) a free radical initiator and optionally acoinitiator and then it is allowed to progress,

c) when the polymerization reaction is complete, one or moreoil-in-water type emulsifying agents are introduced at a temperature ofless than 50° C.

According to one variant of this method the reaction medium derived fromstep b) is concentrated by distillation, before carrying out step c).

According to a preferred embodiment of the method as defined above, thepolymerization reaction is initiated by an oxidation-reduction pairgenerating hydrogen sulphite ions (HSO₃ ⁻), such as the cumenehydroperoxide-sodium metabisulphite (Na₂S₂O₅) pair or the cumenehydroperoxide-thionyl chloride (SOCl₂) pair at a temperature of lessthan or equal to 10° C., if desired accompanied by a polymerizationcoinitiator such as for example azobis(isobutyronitrile), dilaurylperoxide or sodium persulphate and then carried out either almostadiabatically until a temperature greater than or equal to 50° C. isobtained, or by controlling the temperature.

The polyelectrolyte as defined above may be isolated from the precedingself-reversible invert latex by various methods known to persons skilledin the art, such as the precipitation technique which consists inpouring the latex into a large excess of a solvent such as acetone,isopropanol or ethanol, or such as the spray-drying technique which isdescribed in the international publication WO 00/01757 or by azeotropicdehydration.

According to a variant of the methods of preparation as defined above,the polyelectrolyte which is the subject of the present invention isisolated from the self-reversible invert latex.

The polyelectrolyte or the self-reversible invert latex which are thesubject of the present invention may be used for example as a thickenerfor cosmetic or pharmaceutical compositions, as a thickener for printingpastes for the textile industry, as thickeners for industrial orhousehold detergents, as additives for the petroleum industry, as arheology modifier for drilling mud.

By virtue of its cationic character, the polyelectrolyte which is thesubject of the present invention, and the self-reversible invert latexescontaining it, are advantageously used as thickeners and/or asemulsifiers in cosmetic or pharmaceutical compositions intended for haircare and/or conditioning.

Such compositions are usually provided in the form of emulsion ormicroemulsion shampoos and in particular in the case of vaporizableemulsion conditioners.

Accordingly, according to a final aspect, the subject of the inventionis a cosmetic or pharmaceutical composition, characterized in that itcontains, as emulsifying and/or thickening agent, an effective quantityeither of the cationic polyelectrolyte as defined above, or of theself-reversible invert latex containing it.

The cationic polyelectrolytes or the self-reversible invert latexes maybe formulated in cosmetic, dermopharmaceutical or pharmaceuticalformulas such as mousses, gels, lotions, sprays, shampoos, conditioners,lotions for the hands and the body, sunscreens, and more generally incare products.

The following examples illustrate the present invention without howeverlimiting it.

A—EXAMPLES OF PREPARATION OF A SELF-REVERSIBLE INVERT LATEX CONTAININGPOLYELECTROLYTES ACCORDING TO THE INVENTION Example 1 Self-ReversibleInvert Latex of the Copolymer

AM/APTAC/LA(4EO) (84.7/14.9/0.4) crosslinked with MBA

The following are loaded into a beaker, with stirring:

-   -   164.4 g of deionized water,    -   362.1 g of a commercial solution containing 50% of acrylamide        (AM),    -   123.9 g of a commercial solution containing 75% of        acrylamidopropyltrimethylammonium chloride (APTAC)    -   0.070 g of methylene bisacrylamide (MBA),    -   0.45 g of a commercial aqueous solution containing 40% of the        sodium salt of diethylenetriaminepentaacetic acid.

An oily phase is prepared by successively mixing:

-   -   259 g of isohexadecane,    -   20 g of sorbitan isostearate (MONTANE™ 70),    -   5 g of HYPERMER™ 2296 (Uniquema),    -   5 g of tetraethoxylated lauryl acrylate [LA(4EO)],    -   0.1 g of azobis(isobutyronitrile) (AIBN).

The aqueous phase is gradually incorporated into the organic phase andthen subjected to vigorous mechanical stirring by means of anULTRA-TURRAX™ type turbine mixer in order to form an invert emulsion(water/oil).

The emulsion is then cooled to about 10° C. and placed under nitrogenbubbling for about 60 minutes in order to remove oxygen therefrom. Thepolymerization is then initiated by incorporating therein 10 cm³ of asolution of cumene hydroperoxide at 0.68% by weight in isohexadecane.After homogenization of the medium, 25 g of an aqueous sodiummetabisulphite solution at 0.1% by weight are added while allowing thetemperature of the mixture to rise to the final polymerizationtemperature and then leaving the mixture for 90 minutes. The whole isthen cooled to about 35° C., and then 40 g of ethoxylated lauryl alcoholat 7 moles (SIMULSOL™ P7) are added. The desired self-reversible invertlatex is obtained.

Analysis

Polyelectrolyte content: about 27.5% by weight

Measurement of Viscosity

Viscosity of an aqueous solution containing 3% by weight of theself-reversible invert latex (Brookfield RVT, No. 6 rotor; speed: 5revolutions per minute); η=45 000 mPa·s

Viscosity of an aqueous solution containing 3% by weight of theself-reversible invert latex and containing 1% o of sodium chloride

(Brookfield RVT, No. 3 rotor; speed: 5 revolutions per minute); η=1 280mPa·s.

Example 2 Self-Reversible Invert Latex of the Copolymer

Noncrosslinked AM/APTAC/THAM/LA(4EO) (77.7/14.9/7.0/0.4)

The following are loaded into a beaker, with stirring:

-   -   157.6 g of deionized water,    -   332.3 g of a commercial solution containing 50% of acrylamide        (AM),    -   123.9 g of a commercial solution containing 75% of        acrylamidopropyltrimethylammonium chloride (APTAC)    -   36.8 g of tris(hydroxymethyl)acrylamidomethane (THAM),    -   0.45 g of a commercial aqueous solution containing 40% of the        sodium salt of diethylenetriaminepentaacetic acid.

An oily phase is prepared by successively mixing:

-   -   259 g of isohexadecane,    -   20 g of sorbitan isostearate (MONTANE™ 70),    -   5 g of HYPERMER™ 2296 (Uniquema),    -   5 g of tetraethoxylated lauryl acrylate [LA(4EO)],    -   0.1 g of azobis(isobutyronitrile) (AIBN).

The procedure is then carried out according to a procedure identical tothat of Example 1 and the desired self-reversible invert latex isobtained.

Analysis

Polyelectrolyte content: about 29.7% by weight

Measurement of Viscosity

Viscosity of an aqueous solution containing 3% by weight of theself-reversible invert latex (Brookfield RVT, No. 6 rotor; speed: 5revolutions per minute); η=48 200 mPa·s

Viscosity of an aqueous solution containing 3% by weight of theself-reversible invert latex and containing 1% o of sodium chloride

(Brookfield RVT, No. 3 rotor; speed: 5 revolutions per minute); 1=1 760mPa·s.

Example 3 Self-Reversible Invert Latex of the Copolymer

Noncrosslinked AM/APTAC/THAM/LA(4EO) (72.7/19.9/7.0/0.4)

The following are loaded into a beaker, with stirring:

-   -   137.5 g of deionized water,    -   311 g of a commercial solution containing 50% of acrylamide        (AM),    -   165.2 g of a commercial solution containing 75% by weight of        acrylamidopropyltrimethylammonium chloride (APTAC)    -   36.8 g of tris(hydroxymethyl)acrylamidomethane (THAM),    -   0.45 g of a commercial aqueous solution containing 40% of the        sodium salt of diethylenetriaminepentaacetic acid.

An oily phase is prepared by successively mixing:

-   -   259 g of isohexadecane,    -   20 g of sorbitan isostearate (MONTANE™ 70),    -   5 g of HYPERMER™ 2296 (Uniquema),    -   5 g of tetraethoxylated lauryl acrylate [LA(4EO)I,    -   0.1 g of azobis(isobutyronitrile) (AIBN).

The procedure is then carried out according to a procedure identical tothat of Example 1 and the desired self-reversible invert latex isobtained.

Measurement of Viscosity

Viscosity of an aqueous solution containing 3% by weight of theself-reversible invert latex (Brookfield RVT, No. 6 rotor; speed: 5revolutions per minute); η=84 000 mPa·s

Viscosity of an aqueous solution containing 3% by weight of theself-reversible invert latex and containing 1% o of sodium chloride

(Brookfield RVT, No. 3 rotor; speed: 5 revolutions per minute); η=3 560mPa·s.

Examples of Formulations

Example 4 Antistress Hair Care

Formula Phase A Water qs 100% Xanthan gum 0.50% Phase B SEPICAP ™ MP3.00% Phase C Composition of Example 1 4.00% Phase D Butylene glycol5.00% LANOL ™ 99 5.00% SEPICIDE ™ HB 0.30% SEPICIDE ™ CI 0.20% Perfume0.20%Procedure

Disperse the xanthan gum in water with a deflocculating device. Then addSEPICAP™ MP, then the composition of Example 1; disperse it and then addthe ingredients of Phase D.

Example 5 Restructuring Cream Mask for Stressed and Embrittled Hair

Formula Phase A MONTANOV ™ 82 3.00% LANOL ™ P 6.00% AMONYL ™ DM 1.00%Isostearyl isononanoate 5.00% Composition of Example 2 2.50% Phase BWater qs 100% Phase C SEPICAP ™ MP 3.00% SEPICIDE ™ HB 0.30% SEPICIDE ™CI 0.20%Procedure

Melt Phase A at 75° C. Heat Phase B to 75° C. Emulsify A in B. At around40° C., introduce the constituents of Phase C.

Example 6 Purifying Gel for the Face

Formula Phase A MONTALINE ™ C 40 7.00% Pearlescent base 2078 5.00%Composition of Example 3 2.00% Phase B Water qs 100%

Example 7 Colouring Shampoo

Formula Phase A MONTALINE ™ C 40 15.00% Disodium cocamphoacetate 5.00%Cetrimonium chloride 1.00% SEPIPERL ™ N 3.00% Composition of Example 23.00% Phase B Colour qs Water qs 100%

Example 8 Antimicrobial Soap for the Hands

Formula Phase A MONTALINE ™ C 40 20.00% Glycerin 5.00% Composition ofExample 2 1.00% Phase B Water qs 100%

Example 9 Antiseptic Liquid Soap

Formula Phase A MONTALINE ™ C 40 30.00% ORAMIX ™ NS 10 15.00%Chlorhexidine digluconate (at 20%) 5.00% Composition of Example 1 2.00%Phase B Water qs 100%

The definitions of the commercial products used in the examples are thefollowing:

SEPICIDE™ HB is a preserving mixture comprising phenoxyethanol,methylparaben, ethylparaben, propylparaben and butylparaben, marketed bythe company SEPPIC.

SEPICIDE™ CI is imidazolidinylurea, marketed by the company SEPPIC.

ORAMIX™ NS 10: decyl glucoside marketed by SEPPIC.

MONTALINE™ C 40: (cocoammoniumcarbamoyl chloride) marketed by SEPPIC.

SEPIPERL™ N: (cocoyl glucoside/cocoyl alcohol) marketed by SEPPIC.

MONTANOV™ 82: (cocoyl glucoside/cetearyl alcohol) marketed by SEPPIC.

AMONYL™ DM: (quaternium 82) marketed by SEPPIC.

SEPICAP™ MP: (sodium cocoyl amino acids/potassium dimethicone copolyolpanthenyl phosphate) marketed by SEPPIC.

LANOL™ P: (glycol palmitate) marketed by SEPPIC.

LANOL™ 99: (isononyl isononanoate) marketed by SEPPIC.

1. (canceled) 2-15. (canceled)
 16. A linear or crosslinked cationicpolyelectrolyte composition, wherein said composition comprisescopolymerization of at least one cationic monomer with at least oneneutral monomer and at least one nonionic surfactant monomer.
 17. Thecomposition according to claim 16, wherein said neutral monomercomprises at least one component selected from the group consisting of:a) acrylamide, b) methacrylamide, c) vinylpyrrolidone, d)diacetone-acrylamide, e) dimethylacrylamide, f) (2-hydroxyethyl)acrylate, g) (2,3-dihydroxypropyl) acrylate, h) (2-hydroxyethyl)methacrylate, and i) (2,3-dihydroxypropyl) methacrylate.
 18. Thecomposition according to claim 17, wherein said composition furthercomprises an ethoxylated derivative of said component and the molecularweight of said derivative is in the range of from about 400 to about1000.
 19. The composition according to claim 16, wherein said cationicmonomer comprises at least one component selected from the groupconsisting of: a)2,N,N,N-tetramethyl-2-[(1-oxo-2-propenyl)amino]propanammonium chloride(AMPTAC), b) 2,N,N-trimethyl-2-[(1-oxo-2-propenyl)amino]propanammoniumchloride, c) N,N,N-trimethyl-3-[(1-oxo-2-propenyl)amino]propanammoniumchloride (APTAC), d) “diallyldimethylammonium chloride (DADMAC), e) N,N,N-trimethyl-2-[(1-oxo-2-propenyl)]ethanammonium chloride, f)N,N,N-trimethyl-2-[(1-oxo-2-methyl-2-propenyl)]ethanammonium chloride,g) N-[2-(dimethylamino)-1,1-dimethyl]acrylamide,N-[2-(methylamino)-1,1-dimethyl]acrylamide, 2-(dimethylamino)ethylacrylate, h) 2-(dimethylamino)ethyl methacrylate, and i)N-[3-(dimethylamino)propyl]acrylamide.
 20. The composition according toclaim 16, wherein said nonionic surfactant monomers are represented byat least one formula selected from the group consisting of:a) A-C(═C)—O—[(CH₂—CH(R₁)—O]_(n)—R  (I)b) R′—[O—CH(R₁′)—CH₂]_(n)—O—(O═)C-A′-C(═O)—O—[(CH₂—CH(R₁)—O]_(n)R  (I′)wherein said n and said n′ each are in the range of from about 1 toabout 50; wherein said A is an unsaturated aliphatic monovalent radicalcomprising from about 2 to about 6 carbon atoms; wherein said A′ is anunsaturated aliphatic divalent radical comprising from about 2 to about6 carbon atoms; wherein said R₁ and said R′₁ each comprise at least oneat least one component selected from the group consisting of a hydrogenatom, a methyl radical, and an ethyl radical; wherein said R and said R′each comprise an aliphatic hydrocarbon radical which is saturated,unsaturated, linear, or branched; and wherein said aliphatic hydrocarbonradicals of said R and said R′ each further comprise from about a toabout 30 carbon atoms.
 21. The composition according to claim 20,wherein said A comprises at least one component selected from the groupconsisting of: a) vinyl radical, and b) 2-propenyl radical.
 22. Thecomposition according to claim 20, wherein said A′ comprises at leastone component selected from the group consisting of: a) 1,2-ethenediylradical, and b) 2-propene-1,2-diyl radical.
 23. The compositionaccording to claim 20, wherein said aliphatic hydrocarbon radicals ofsaid R and said R′ each comprise from about 8 to about 18 carbon atoms.24. The composition according to claim 20, wherein said R and said R′each comprise at least one linear primary alcohol selected from thegroup consisting of: a) octyl, b) pelargonic, c) decyl, d) undecyl, e)undecenyl, f) lauryl, g) tridecyl, h) myristyl, i) pentadecyl, i) cetyl,k) heptadecyl, l) stearyl, m) oleyl, n) linoleyl, o) nonadecyl, p)arachidyl, q) behenyl, and r) erucyl.
 25. The composition according toclaim 20, wherein said R and said R′ each comprise at least one1-triacontenoic alcohol selected from the group consisting of: a) octyl,b) nonyl, c) decyl, d) undecyl, e) 10-undecenyl, f) dodecyl, g)tridecyl, h) tetradecyl, i) pentadecyl, j) hexadecyl, k) heptadecyl, i)octadecyl, m) octadecenyl, n) 10,12-octadecadienyl, o) 13-docosenyl, andp) triacontanyl radicals.
 26. The composition according to claim 20,wherein said R₁ and R′₁ each further comprise a hydrogen atom.
 27. Thecomposition according to claim 20, wherein said n and n′ each comprise arange of from about 1 to about
 10. 28. The composition according toclaim 16, wherein said composition comprises: a) from about 5% to about35% of said cationic monomer; b) from about 55% to about 95% of saidneutral monomer; and c) from about 0.1% to about 5% of said nonionicsurfactant monomer, wherein said percentages of each monomer areexpressed in terms of monomeric units.
 29. The composition according toclaim 28, wherein said composition further comprises a non-zeroproportion of N-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]propenamidemonomer.
 30. The composition according to claim 29, wherein saidcomposition comprises: a) from about 5% to about 35% of a cationicmonomer; b) from about 35% to about 91% of a neutral monomer; c) fromabout 0.1% to about 5% of a nonionic surfactant monomer; and d) fromabout 3% to about 20% of aN-[2-hydroxy-1,1-bis(hydroxymethyl)ethyl]propenamide monomer, whereinsaid percentages of each monomer are expressed in terms of monomericunits.
 31. The composition according to claim 30, wherein saidcomposition is not crosslinked.
 32. The composition according to claim30, wherein said composition is crosslinked.
 33. The compositionaccording to claim 32, wherein said crosslinked agent is selected fromthe group consisting of: a) diethylene, b) polyethylenic compounds, c)diallyloxyacetic acid, d) sodium salt, e) triallylamine, f) trimethylolpropanetriacrylate, g) ethylene glycol dimethacrylate, h) diethyleneglycol diacrylate i) diallylurea, and j) methylene bis(acrylamide). 34.The composition according to claim 33, wherein the molar proportion ofsaid crosslinked agent is in the range of from about 0.005% to about 1%of the total composition.
 35. The composition according to claim 34,wherein said proportion is in the range of from about 0.01% to about0.2%.
 36. The composition according to claim 35, wherein said proportionis in the range of from about 0.01% to about 0.1%.
 37. The compositionaccording to claim 18, wherein said composition may be utilized for atleast one function selected from the group consisting of: a) a thickeneror an emulsifier for cosmetic or pharmaceutical formulations; b) athickener or an emulsifier for printing pastes for the textile industry;c) a thickener or ran emulsifier for industrial or household detergents;d) an additive for the petroleum industry; and e) a rheology modifierfor drilling mud.
 38. The composition according to claim 16, whereinsaid formulation comprise hair care products.
 39. A method for preparinga linear or crosslinked cationic polyelectrolyte composition comprisingcopolymerizing at least one cationic monomer with at least one neutralmonomer and at least one nonionic surfactant monomer.
 40. A method forpreparing a self-reversible invert latex comprising the steps of: a)emulsifying monomers in an aqueous solution in the presence of at leastone water-in-oil type emulsifying agent and a nonionic surfactantmonomer; b) initiating a polymerization reaction by introducing anemulsion formed in step i) and a free radical initiator; and c)introducing at least one oil-in-water type emulsifying agent when thepolymerization reaction is complete.
 41. The method according to claim40, wherein said method further comprises emulsifying additives.
 42. Themethod according to claim 40, wherein said method further comprisesadding a coinitiator.
 43. The method according to claim 40, wherein thestep of introducing at least one oil-in-water type emulsifying agentoccurs at a temperature of less than about 50° C.
 44. The methodaccording to claim 40, wherein step (ii) further comprises distillationbefore introducing at least one oil-in-water type emulsifying agent. 45.The method according to claim 40, wherein said polymerization reactionis initiated by an oxidation-reduction pair generating hydrogen sulphiteions (HSO₃ ⁻).
 46. The method according to claim 45, wherein saidhydrogen sulphite ions (HSO₃ ⁻) comprises at least one componentselected from the group consisting of: a) cumene hydroperoxide-sodiummetabisulphite (Na₂S₂O₅) pair; and b) cumenehydroperoxide-thionyl-chloride (SOCl₂) pair.